Spark-plug for explosive-engines.



I M. T. MINOGUE.

SPARK PLUG FOR EXPLOSIVE ENGINES APPLICATION FILED AUG. a, 19:2.

1,1 1 9,302, Patented Dec. 1, 1.914.

INVENTOR WlTNEssEs MARTN. T lNOCxUE MJM BY ms ATTORNEY UNITED STATES li'ATENT- FFICE.

MARTIN T. MINQGUE, OF IPHILADELPHIA, PENNSYLVANIA, ASEIG'NOR, BY MESNE ASSIGNMENTS, TO SUPERIOR MOTOR SPECIALTY GGMPENY, A. CORPORATION 012 DELAWARE.

SPARK-PLUG FOR EXPLOSIVEJINGINES.

-Appli'eation filed August 8,

To all whom it may concern."

Be it known that I, MARTIN T..Mmoonn, a citizen of the United States, residing in Philadelphia, Pennsylvania, have invented certain-Improvements in Spark-Plugs for Explosive-Engines, of which the following is a specification.

One object of my invention is to so construct a spark plug for explosive engines as to simplify the construction of the porcelain member thereof, to permit of the ready application of the electrodes thereto and their secure retention therein, to insure good electrical contact between. the electrodes and the binding posts at the outer end of the plug, to provide simple and efi'ectivve means for securing the porcelain memher in the surrounding metallic sleeve or shell, and to permit of the use of theplug either as a single spark plug or as a double spark plug. y

A further objectof my invention is to so construct a spark plug a's to permit of the use of-the same for the introduction of fluid under pressure into the cylinder of the engine forstarting purposes; another object is to effect the secure confinement of the plug to the cylinder and the ready re lease of the plug therefrom, and a final object is to provide for the use of two plugs in the cylinder so as to effect a double sparking therein.

These objects I attain in the manner hereinafter set forth, reference being had to the accompanying drawing, 'in which- Figure 1 is a vertical section of a spark plug constructedin accordance with my invention, showing the'same as designed for a double spark plug; Fig. 2 is a horizontal section, on a smaller scale, on the line a-a, Fig. 1; Fig. 3 is a sectional view showing the electrodes as isposed when the spark is intended for use as a single spark plug; Fig. 4 is a horizontal section on the line bb, Fig. 1; Fig. 5 is a horizontal section of part of the plug on the line cc, Fig. 1, and Fig. 6 is a diagram illustrating the electrical connections whereby the use of two plugs in the cylinder is permitted for the purpose of insuring double sparking in said cylinder.

In Fig. 1 of the drawing, 1 represents a tubular casing which carries the spark plug, this easing being screwed into the head of the cylinder and being in electrical contact therewith. The bore of the casing l Specification of Letters Patent.

Patented Dec. 1, 19M.

1912. Serial No. 71-1.,015;

celain. is, as to its lower portion, contained within the sleeve 2 and has formed in it an external groove 6 which registers with a corresponding internal groove 7' in the sleeve 2 .so as to form a chamber for the reception of a/split ring 8, the bitter having a normal tendency to expand so to enter the groove inthe s eeve 2 withhzt leaving the groove in the porcelain menilmr 5, thereby firmly locking said porcelah member to the sleeve In the first instance the split ring 8 is compressed into the groove 6 of the porcelain member so as to be contained wholly within the latter, and said porcelain member is thenpushed down into the sleeve 2 until the grooves 6 and 7 are in register, whereupon the ring will expand into the groove 7 and lock the porcel in member and sleeve together, as indica ed in Fig. 1. Escape of gas through the space between the porcelain member 5 and the sleeve 9 is prcventedby a filling 3 of cement.

In preparing the porcelain member 5 for rthe reception of the electrodes 9, two "ertical openings of a diameter large enough to receive the electrodes are formed therein. and theseopeningsare crossed at a little distance below the tops of the same by transverse recesses 10 formed in the upper por tion of the porcelain member 5 and of such depth that a bridge wall. 5 of porcelain interposed between the two recesses so as to effectively insuiatc their electrically ne from the other. Each of the recesses l0 receives one of the binding posts 11 05 the plug, and each of these posts has. at its inner end, a head 12 with opening therethrough for the passage of the electrode 9 which is pushe up from the lower end of the plug until the upper end of said electrode passes through the head 12 and enters the upper end of the vertical opening formed in theporcelain member for its reception, lateral strain being then exerted upon the binding post 11 so as to draw its head firmly into contact with that portion of the electrode which bridges the opening 10 and thereby insure good o em-icul contact between the binding post nj'nl the electrode. To efiect this lateral Stllll upon the binding post the was is threaded through-' the face of the porcelain member 5 is in- .terposed a washer 15, the threaded portion of the binding post also having another nut 16, which, in conjunction with the nut H, serves to firmly confine the conducting wire to the binding post 11. The recesses 10 are preerably of considerably greater diameter than the binding posts 11, and after the binding post has been inserted in the recess and its head engaged with the electrode 13 the recess maybe filled with anysuitable cement prior to the application of the washer 15 and nut 14. Both the openings for the reception of the electrodes and the recesses for the reception of the binding posts are straight bored, and can thus bereadily formed in the porcelain member. while the latter is-in the plastic condition before being burned, the manufacture of the porcelain member being thereby simplified and cheapened.

Firmly secured to the casing l by-means' of a nut 17 and washers 18 is a ring 19 having threaded openings for the reception of clamp screws 20 which pass through openings in a pair of jaws 2l,'and have enlarged heads 2:2 rounded on the under sides, and bearing upon concaved or dished washers on the jaws "21, so that when the screws 20 are turned in one direction the jaws 21, which overlap the top of the sleeve 2, will be pressed down upon the latter so as toconfine the same firmly to the casing 1, the turning of the screws 20 in the opposite direction relieving the sleeve 2 from'the ressure of the jaws 21 and permitting the utter to turned to a position out of engagemen with said sleeve 2, thus permittingthe latter and the porcelain mem-- ber carried by it to be withdrawn from the casing 1 when it becomes necessary to inspect or change the parkplugs for any reason. Each of the; electrodes is curved at that end which projects below the porce lain membery5, so that by turning each electrode in'the porcelain member the curved lower ends of said electrodes may be caused to extend outwardly, as in Fig. 1, or inwardly as in Fig. 3, each electrode, in the former case, being independent of the other and forming the spark between its lower end and the adjacent wall of the sleeve 2, while when the electrodes are adjusted as shown in Fig. 3, they cooperate with each other and form the spark between their adjoining ends. In the latter case the upper end of one of the electrodes will be connected to the positive pole of the electric generator and the upper end of the other electrode will be connected to the negative pole of the while when the electrodes are ad usted 'larspace ergy,

ently, the upper end of each electrode may be connected to one pole of an electric generator and the o posite pole of the same may be connecte to the cylinder or other ground connection, which is in electrical connection with the' sleeve 2' through the casing 1.

When the double spark plug shown in Fig. 1 is used it is not intended that both of the electrodes shall be connected to the electric generator at one time, only one electrode being u'sed ata time and the other beingbrought into use in theevent of the first being rendered inoperative at any time from any cause, and one electi'o e may besupplied with current from one electric generator, as, for instance, a'battery, while the other electrode may be supplied with current from another electri'c generator, as, for instance, a magneto. The current from the battery will usually act as a primary for a sparking coi'l, the current from the secondary coil forming the spark, and the magneto will either act in the same way, or,

it of sufficiently high intensity, will be con-' nected directly to the spark plug. 7

It is nowa common practice to start an explosive engineby introducing fluid under pressure into one or-more of the cylinders instead of. crankingthe engine, as was formerly customary. Iemploy the ring 19 as a means for efi'ecting the fluid connection, said ring 19 having, at one side, an inter-- nally threaded nipple 2 4 communicating through a passage 25 with an internal groove 26in the ring, the base of the nipple being provided with a-valve seat 27 for the reception of a ,valve 28' which prevents back flow through the nipple but does not interfere with forward flow therethrou'gh. The groove 26 communicates through one or more openings-in the casing lwith the annubetween said casing and the sleeve 2,.so as to provide for the flow of fluid under pressure into the cylinder through this space.

In Fig. 6 I have shown in diagrammatic form the use of my improved spark plug for the. production of a double spark'in the cylinder, In this figure, 30" represents the battery, 31 the magneto, 32 the spark'coil, 33 and 34.- the two spark'plugs, and .35 a switch' whereby either the battery orv the magneto maybe utilized as the source of electric enit being understood that the circuits will be employed in connection with the customary commutator for properly timing the sparking of the engine. The plug 351 has its electrodes adjusted so as to act as a single spark plug, and the plug 33 has its electrodes adjusted so as to act as-a double spark plug. When the circuit is closed the current enters the plug 34 at one binding post, forms a spark between the electrodes of said plug, passes thence from the other binding Ill post and through a, connection 36 to a bind? ing post of the plug 33 and'formsa s ark between the corresponding electrode an the sleeve .2 of the plug, which-is grounded .5 through the cylinder. When the current is not grounded through thecyli'nder, both of the plugs may be similar to the'plug 34, the lugs being connected as at 36 and one plug eing conneotedto the positive pole and the other to the negative pole of the generator.

I claim: I

1, In a spark plug for-explosive engines, an insulating member having a longitudinal bore therethrough, an electrode extending loosely through said bore, a transverse recess crossing said bore and into which said electrode extends, a -hinding'post projecting into said recess and having its inner end engag ing the electrode, said inner end being of less diameter than said transverse recess, and means for imparting endwise movement to said binding post, to cause it to bind upon the electrode and bend the same at a point in said recess and thus make a 00d electrical contact as well as lock t e electrode against removal.

I 2. In a spark plug, the combination of 'an insulating body having a longitudinal bore, said bore having a transverse recess crossing it, a bendable electrode extending loosely through said bore and entering saidrecess, a." binding post extending into said recess and engaging said electrode, the part that engages the electrode being less in diameter than said transverse rece'ss, the-binding post having a' threaded stem'and a pair of nuts on' the latter, one for imparting endwise movement to the binding. post to bend the electrode" at, a point in said and the other foreonfining the conducting Wire to the binding post, an hbutment being providedqfor the former nut.

3. In a spark plug for explosive. engines, aninsulating member having a straight bore therein forthe reeeption of an elee Hi5 u transverse recess connnuniceimg wit. Isuial bore and extending inwardly beyond the same, a perforated binding post contained in said recess, an electrode contained in said bore and projecting into the perforation o1? the binding 'post and means for imparting outward draft to said binding post so. as to cause it to bear :igeizestseid eleetrede.

t; In a spar-kph: for 'explesive engines, an insulating rue-timer having therein a straight bore and transverse recess, the bore crossing the r so as to present a portion on each i wof, end thereof extending illlufli'i end the i forated binding g ned cess, an electrode own .11

extendim across the r ,s and perforation C). the o g KATE A. BEADLE, HAMILTON D. TURNER. 

